AK hitsTPTK on turn. Turn bet too weak?

[niteswmer]

Villain is 14.8/5/.79 over only 280 hands. I raise PF, follow-up with a CB, get called, then hit my K on the turn. Is my turn bet so weak that I induce villain to call with a flush draw? As played, do I call the river? With such a low aggression factor, does villain always have a hand that beats TPTK here?

Full Tilt No-Limit Hold'em, $0.50 BB (8 handed) Full-Tilt Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

MP1 ($60.90)
Hero ($49.50)
CO ($22.20)
Button ($10.60)
SB ($41.30)
BB ($12.95)
UTG ($49.85)
UTG+1 ($53.45)

Preflop: Hero is MP2 with A, K. SB posts a blind of $0.50.
BB calls $0.50, UTG calls $0.50, 2 folds</font>, Hero raises to $2.5</font>, 3 folds</font>, BB folds, UTG calls $2.

Flop: ($6) 9, 6, 2 (2 players)</font>
UTG checks, Hero bets $4</font>, UTG calls $4.

Turn: ($14) K (2 players)</font>
UTG checks, Hero bets $8</font>, UTG calls $8.

River: ($30) 3 (2 players)</font>
UTG bets $15</font>, Hero ???.